Lake Tahoe

Lake Tahoe is a large freshwater lake in the Sierra Nevada of the United States. At a surface elevation of 6,225 ft (1,897 m), it is located along the border between California and Nevada, west of Carson City. Lake Tahoe is the largest alpine lake in North America. Its depth is 1,645 ft (501 m), making it the second-deepest in the United States (the deepest is Crater Lake in Oregon at 1,945 ft (593 m), 300 ft (91 m) deeper). Additionally, Lake Tahoe is listed as the 27th largest lake by volume in the world at 122,160,280 acre·ft.
The lake was formed about 2 million years ago and is a part of the Lake Tahoe Basin with the modern lake being shaped during the ice ages. It is known for the clarity of its water and the panorama of surrounding mountains on all sides. The area surrounding the lake is also referred to as Lake Tahoe, or simply Tahoe. More than 75% of the lake's watershed is national forest land, comprising the Lake Tahoe Basin Management Unit of the United States Forest Service.
Lake Tahoe is a major tourist attraction in both Nevada and California. It is home to a number of ski resorts, summer outdoor recreation, and tourist attractions. Snow and skiing are a significant part of the area's economy and reputation. Mountain and lake scenery are attractions throughout the year. The Nevada side also includes large casinos. Highways provide year-round access from Reno, Carson City, and Sacramento.

Lake Tahoe is fed by 63 tributaries, which drain an area about the same size as the lake; half the water entering the lake is rain falling directly on it.
The Truckee River is the lake's only outlet. The Truckee flows northeast through Reno, Nevada, and into Pyramid Lake, Nevada, which has no outlet. Only one third of the water that leaves the lake leaves via the Truckee, however; the rest evaporates from the lake's vast surface.
The flow of the Truckee River and the height of the lake are controlled by a dam at the outlet.